Convertible rail-highway vehicle

ABSTRACT

A conventional highway bus is adapted for alternate use on highways and railways by providing rail conversion units located adjacent respective road wheels of the bus. The conversion units raise the front of the bus on rail wheels to a position which deactivates the front road wheels and the rear of the bus is supported by rail wheels only to the extent that it is guided on the rails but propulsion and some braking is obtained through contact between the rails and the rear road wheels. Air bellows suspension is provided on the rail conversion units to simulate road driving characteristics and hydraulic cylinders permit the rail wheels to be withdrawn upwardly out of service during road operation.

United States Patent [151 3,701,323

Cox 51 Oct. 31, 1972 [54] CONVERTIBLE RAIL-HIGHWAY VEHICLE [72]Inventor: Edwin W. Cox, North Kansas City,

[7 3] Assignee: W. T. Cox Company, Camdenton,

[22] Filed: Nov. 16, 1970 [21] Appl. No.: 97,406

[52] US. Cl. ..105/215 C, 104/245 [51] Int. Cl ..B61d 15/00, B61f 9/00,B62d 61/12 [58] Field of Search ..105/2l5 C; 104/245 [56] ReferencesCited UNITED STATES PATENTS 1,973,494 9/1934 McCullough et al...l05/2l5C 3,342,141 9/1967 Browne ..105/215 C 3,228,350 1/1966 Cox ..l05/215 C3,263,628 8/1966 Grove et a1. ..105/2l5 C Primary Examiner-Gerald M.Forlenza Assistant Examiner-Howard Beltran Attorney-Fishbum, Gold Litman[5 7] ABSTRACT A conventional highway bus is adapted for alternate useon highways and railways by providing rail conversion units locatedadjacent respective road wheels of the bus. The conversion units raisethe front of the bus on rail wheels to a position which deactivates thefrom road wheels and the rear of the bus is supported by rail wheelsonly to the extent that it is guided on the rails but propulsion andsome braking is obtained through contact between the rails and the rearroad wheels. Air bellows suspension is provided on the rail conversionunits to simulate road driving characteristics and hydraulic cylinderspermit the rail wheels to be withdrawn upwardly out of service duringroad operation.

7 Claims, 4 Drawing Figures PATENTEnncI 3 1 m2 SHEEI 2 BF 2 INVENTOR.Edwin W. Cox BY /Q -M 1, 4 ATTORNEYS CONVERTIBLE RAIL-HIGHWAY VEHICLEThis invention relates to convertible rail-highway vehicles and moreparticularly to such vehicles particularly adapted to carry passengersalternately over roads and rails at relatively high speed in comfort.

Vehicles adapted to be used alternately on rails and paved roadways areknown. However, such vehicles generally have been used in connectionwith trucks, construction or railroad maintenance equipment and do notmeet the requirements of speed and comfort for commercial passengerservice. This invention calls for the use of well known commercialbuses, such as those commonly used by public transit companies, whichhave been converted to alternate use on standard rails with conversionunits compatable with, and operated partially through, the standard airsuspension system carried by the bus.

It is the principal objects of the present invention to provide avehicle for alternate use on rails and on roads which is suitable forcarrying large numbers of passengers at relatively high speeds and incomfort; to provide such a vehicle that utilizes the conventional powertrain to the rear wheels for driving and partially braking the vehiclewhile on rails; to provide such apparatus wherein the rail units areeasily withdrawn into an inoperative position when the vehicle is usedon roads; and to provide such a vehicle which utilizes a portion of theexisting suspension system for the rail mechanism function.

Other objects and advantages of this invention will become apparent fromthe following description taken in connection with the accompanyingdrawings wherein are set forth by way of illustration and examplecertain embodiments of this invention.

FIG. 1 is a side elevational view showing a rail bus embodying thisinvention operating upon rails.

FIG. 2 is a fragmentary cross-sectional view taken on the line 2-2, FIG.1, on an enlarged scale, showing apparatus for converting the bus torail operation.

FIG. 3 is a fragmentary side elevation on the scale of FIG. 2particularly showing the relationship between the rear bus wheelsuspension and the rear rail converting structure.

FIG. 4 is a schematic diagram of the hydraulic and compressed airsystems used in connection with the convertible rail bus.

Referring to the drawings in more detail:

The reference numeral 1 generally indicates a passenger carryingvehicle, such as a standard inter-city coach manufactured by GeneralMotors Corporation, having a rear engine and air suspension. In thepractice of this invention, the coach or vehicle 1 is convertible to runalternately on standard railroad tracks and on the road.

The vehicle 1 has a frame 2, front road wheels 3 and rear driven wheels4. The rear wheels 4 are dual, including inner tires 5 and outer tires 6which, during normal road operation, all contact the ground. The innertires 5 are spaced apart a distance suitable for simultaneous engagementwith respective rails 7 and 8 of standard 56% inch gauge. Referringparticularly to FIG. 3, radius rods 9 and 10, typical of other wheelstructure, are pivotally connected at one end thereof to a portion ofthe frame 2 at 11 and 12. At the other end thereof, the rods 9 and areconnected to suspension support 13 which is secured to the rear axlehousing 14.

Vertical loads are supported by rubber and nylon fabric air bellows 15installed between the suspension support 13 and the coach frame 2. Innormal use the pressure in the air bellows 15 is varied automatically inproportion to vehicle load by conventional height control valves 16(FIG. 4), two of which are located at the rear of the bus and onenormally at the front. The height control valves 16 each include a valvelever 17 connected by suitable links (not shown) to the axle foraltering the pressure in the bellows 15 as vehicle load varies. It isnoted that the height control valves 16 are of the known type which donot respond to rapid relative motion between the axles and frame, suchas that caused by road bumps. Telescoping type double-acting shockabsorbers 18 are mounted at the ends of each axle for reducing thetransmission of road shocks to the vehicle body.

The air suspension system of the vehicle 1 includes a pump 19 whichmaintains air under a predetermined pressure in a suspension air tank 20through a suitable regulating valve 21 and check valve 22. Suitable airlines 23 conduct air under pressure from the suspension air tank 20through the height control valve 16 and into distribution lines 24 wherethe air is introduced into the respective bellows l5.

The rail conversion units are broadly designated 25 and comprise asingle vertical leg 26 incorporating an hydraulic cylinder adapted tovertically raise and lower a piston rod or ram 27. A rocker arm 28 iscentrally pivoted about the lower end of the ram 27, permitting limitedrotation in a vertical plane. Suitable rail wheels 29 and 30 are mountedin tandom on the ends of the rocker arm 28 and thereby have some freedomto ride independently over obstacles or rail vertical discon tinuties.The rocker arm 28 is also free to rotate over a limited range with theram 27 in a horizontal plane whereby cooperating rail wheels areoriented in steer around curves. The applied steering sideload impartedthrough the rail wheel flanges by the outside rail on a curve istransmitted across to the inside wheels through twin lateral tie rods 31(FIG. 2) connected to the opposite rocker arms.

Radius rods 32 and 33 are pivotally connected at opposite ends thereof,in the manner described in connection with the radius rods 9 and 10, tosupport the leg 26 and rail wheels associated therewith, but permitsubstantial vertical motion with respect to the bus frame 2.

A suspension support 34 is secured to the leg 26 and extendslongitudinally forwardly and rearwardly with respect to the vehicle 1forming platforms for receiving the lower ends of the air bellows 35.The upper ends of the air bellows 35 are fixed with respect to the frame2, whereby air cushioned support is provided for the rail wheels, aswell as the road wheels.

Referring to FIG. 4, air distribution lines 24 of the conventional busair suspension system is connected through lines 36 to height controlvalves 37, comparable to the valves 16 noted above. The valves 37 areoperated through suitable sensing devices 38 which, in this example,include rods 39 which monitor the relative positions between the frame 2and the respective leg 26. The rods 39 operate through contact withopposite ends of a rigid cross member 40 which provides rigid structuralintegration between opposite legs 26. The height control valves 37 feedcompressed air, as

necessary, into the respective air bellows 35 through suitable airdistribution lines 41. The cross member 40 also serves to providecontact points for shock absorbers 42 which act in conjunction with thebellows 35 to impart riding characteristics to the frame 2 similar tothat which would be experienced through the conventional road suspensionsystem, even though the vehicle is supported primarily on rails.

The hydraulic cylinders associated with the legs 26 are operated throughan hydraulic system consisting of a pump 43, overload bypass valve 44,reservoir 45, dis tribution lines 46 and individual control valves 47.Controls may be conveniently placed within reach of the bus operator.During road operation, the rail wheels 29 and 30 are withdrawn to theposition indicated by the broken lines in FIG. 3. A disc brake 48 isinstalled on each of the rail wheels and may be operated through the busair brake system with the regular operator brake pedal (not shown).

The rail conversion units may be installed in a conventional bus with aminimum of alteration in standard equipment. In operation, when it isdesired to move the vehicle along rails, alignment is made over therails and front rail conversion units are actuated to lift the frontelevated condition by suitable hook structure (not shown). The rear railconversion units are extended downwardly to a point where the bus rearaxle load is generally equally shared between the rear rail units andthe bus rear wheels, causing substantial contact between the inner tires5 and the rails 7 and 8, FIG. 2. The contact between the inner tires 5and the rail is utilized to accelerate the bus through the conventionalpower train while braking is accomplished through the standard rearbrakes of the bus in combination with the braking force availablethrough the disc brakes 48 on the eight rail contacting wheels. Therelative loads assumed by the bellows 15 and 35 at the rear of the busmay be easily controlled to maintain the optimum support distributionbetween rail wheel support and rear tire contact.

It is to be understood that while one form of this invention has beenillustrated and described, it is not to be limited thereto exceptinsofar as such limitations are included in the following claims.

What 1 claim and desire to secure by Letters Patent is:

1. A passenger carrying vehicle for alternate use on rails and on thehighway comprising:

a. a multi-passenger road coach having a frame and front road wheels andrear driven road wheels, said rear road wheels being laterallyspaced-apart a distance suitable for engagement with standard rails, anair suspension system between said frame and road wheels and includingvertically extensible air bellows for maintaining a constant ride heightfor road use regardless of load and load distribution in said coach,said air suspension system including a source of compressed air forsupplying air under pressure to said air bellows,

b. front and rear rail conversion units mounted on said frame andrespectively located adjacent said front and rear road wheels, saidconversion units assembly including a rail wheel mounted on the lowerend of each of said extensible members,

. support means mounted on each of said extensible members, verticallyextensible air bellows positioned between said support means and saidframe, said last named air bellows being operably connected to saidsource of compressed air for resiliently supporting a portion of theweight of said vehicle on said rail wheels when said extensible membersare extended, and i an air valve assembly operably connected betweensaid source of compressed air and said rear conversion unit air bellows,said air valve assembly including a sensing control member responsive tothe relative positions between said frame and said rear conversion unitsupport means, whereby a predetermined load distribution is maintainedbetween said rear road wheels and said rear conversion unit rail wheels.

2. The vehicle as set forth in claim 1, wherein:

a. said extensible member includes an hydraulic cylinder, and

b. said coach includes a source of hydraulic fluid under pressure foroperating said hydraulic cylinder.

3.-The vehicle as set forth in claim 1, wherein:

a. said rail wheel assemblies comprise a horizontal rocker arm havingopposite ends and centrally pivoted about each of said extensiblemembers for rocking in a vertical plane.

. one of said rail wheels being mounted on each of said rocker arm ends.

The vehicle as set forth in claim 3, wherein:

. said respective rocker arms are located in laterally opposed relation;and

b. lateral tie rods are connected to said opposed rocker arms.

5. The vehicle as set forth in claim 1 wherein:

a. said support means comprises a cross beam directed longitudinally ofsaid vehicle and one of said air bellows is positioned at each end ofsaid 'cross beam.

6. The vehicle as set forth in claim 1, including shock absorbers.operably mounted between each of said rail conversion units and saidframe.

7. in combination with a road passenger carrying vehicle having airsuspension and a frame:

a. front and rear rail conversion units movably mounted on said framefor alternately supporting said vehicle on rails,

b. said conversion units each including an extensible member providingselective vertical extension of rail wheels beneath said frame, airbellows between said extensible members and said frame for imparting airsuspension to said vehicle when on rails, and

c. means associated with said rear conversion. units and responsive tothe relative positions between said frame and said rear conversion unitextensible members for operating said air bellows.

1. A passenger carrying vehicle for alternate use on rails and on thehighway comprising: a. a multi-passenger road coach having a frame andfront road wheels and rear driven road wheels, said rear road wheelsbeing laterally spaced-apart a distance suitable for engagement withstandard rails, an air suspension system between said frame and roadwheels and including vertically extensible air bellows for maintaining aconstant ride height for road use regardless of load and loaddistribution in said coach, said air suspension system including asource of compressed air for supplying air under pressure to said airbellows, b. front and rear rail conversion units mounted on said frameand respectively located adjacent said front and rear road wheels, saidconversion units each including an extensible member adapted forvertical extension beneath said frame, a rail wheel assembly including arail wheel mounted on the lower end of each of said extensible members,c. support means mounted on each of said extensible members, verticallyextensible air bellows positioned between said support means and saidframe, said last named air bellows being operably connected to saidsource of compressed air for resiliently supporting a portion of theweight of said vehicle on said rail wheels when said extensible membersare extended, and d. an air valve assembly operably connected betweensaid source of compressed air and said rear conversion unit air bellows,said air valve assembly including a sensing control Member responsive tothe relative positions between said frame and said rear conversion unitsupport means, whereby a predetermined load distribution is maintainedbetween said rear road wheels and said rear conversion unit rail wheels.2. The vehicle as set forth in claim 1, wherein: a. said extensiblemember includes an hydraulic cylinder, and b. said coach includes asource of hydraulic fluid under pressure for operating said hydrauliccylinder.
 3. The vehicle as set forth in claim 1, wherein: a. said railwheel assemblies comprise a horizontal rocker arm having opposite endsand centrally pivoted about each of said extensible members for rockingin a vertical plane. b. one of said rail wheels being mounted on each ofsaid rocker arm ends.
 4. The vehicle as set forth in claim 3, wherein:a. said respective rocker arms are located in laterally opposedrelation; and b. lateral tie rods are connected to said opposed rockerarms.
 5. The vehicle as set forth in claim 1 wherein: a. said supportmeans comprises a cross beam directed longitudinally of said vehicle andone of said air bellows is positioned at each end of said cross beam. 6.The vehicle as set forth in claim 1, including shock absorbers operablymounted between each of said rail conversion units and said frame.
 7. Incombination with a road passenger carrying vehicle having air suspensionand a frame: a. front and rear rail conversion units movably mounted onsaid frame for alternately supporting said vehicle on rails, b. saidconversion units each including an extensible member providing selectivevertical extension of rail wheels beneath said frame, air bellowsbetween said extensible members and said frame for imparting airsuspension to said vehicle when on rails, and c. means associated withsaid rear conversion units and responsive to the relative positionsbetween said frame and said rear conversion unit extensible members foroperating said air bellows.